I run Evans in my 84 & 85 M-B diesel cars. So far no issues. Jay Leno uses it in his entire fleet. My son drove the 1984 over the I-5 pass to LA last summer and it only briefly hit 105 C, then decreased (redline at 120 C). That is the max I ever saw when running 50/50 green stuff. I hear manufacturers test new cars on that stretch on a hot day as a "worst-case" condition for the U.S. Otherwise, it always runs close to the 82 C thermostat. My 1985 has a slight issue. It seems to want to run almost 90 C all the time, perhaps since I changed to Evans (not sure), but also now in the winter even on cold mornings, so I suspect a problem with the thermostat (or dash gage). My son has that car now, so little time to investigate. The symptoms don't suggest the change to Evans is the reason.
I also converted our 2002 3.8L minivan to Evans last summer while my wife was away for a month. It has rear heat, so more involved. I also changed all heater hoses (it has many) to silicone since 15 yrs old and I don't want to lose the valuable Evans. No issues with overheating. In all cars, I allowed a long time so the water could evaporate. The heater cores are toughest. I first blew them out, then ran some ethanol thru, then left on an "apnia pump" (for fat people to sleep, not me, bought cheap at garage sale) puffing thru for a week until no more alcohol smell. Best way to clear the heater core is to connect air, hold the other tube w/ thumb to build pressure, then release to get a forceful puff, repeat. Also works for radiators. No need to remove block plugs (aka "freeze"), though if doing so anyway, that is an opportune time to switch. Of course, I removed the block drains and radiator hoses, water pump, ... and puffed thru the block until no water, then ran the engine for short intervals to heat the block. Before all that, flush all corrosion. I use water w/ citric acid. You don't want to invest in Evans for a rusty system. Once installed, it should never rust again. It would be a bad day if the rear plug on my small block rusted thru. I have been airing out my 64 Valiant engine for many months while doing other things (plus new heater core), then Evans. If you convert, smartest to wait for when you are doing other jobs. A lot of people denigrate Evans, mostly those who don't use it. Same for the silicone brake fluid I use in most cars. I am not a hater, but must admit to hating corrosion.